Making Saltwater - How Much To Mix?

[sophos9]

Hi, making my first batch of saltwater in a 20ltr food safe container

I was working on the assumption (PFK info) that amount 32g per litre of water should give you a salinity if 1.023. I've added 650g and measured, the salinity is 1.005??

How long does it take for the salt to dissolve - there is not much in the bottom of the container. This is the product >> linky

Oh and who are TAP anyway?

Many thanks

 

[zeo]

wow thats some cheap salt.

 

[SkiFletch]

That's becuase while 32g of pure salt with one gallon of water will give an appropriate specific gravity, saltwater mixes that we use on our tanks are not all salt. There are calcium, carbonate, magnesium, and other trace elements in the salt mix which all remove a percentage of the weight of NaCl. Each salt mix should have its own instructions on how much mix per how many litres/gallons of water. The general rule of thumb is 1/2 cup per gallon, but each mix is a little different. Yours says it makes 60L total of saltwater, so if you wanted to make 20L of water, mix up 1/3rd of the bag in 20L of water and you'll be set

 

[zeo]

Please post remember to post a reply on how you get on with this salt. I'm on dire need of the stuff and that seems to be the cheapest I've seen online!

 

[sophos9]

Thanks for the replies...

Ok, I kinda lied, this is the one >> linky

Now it says 24kg makes 720ltrs so 24kg/720ltr = 0.03g per ltr

20ltr * 0.03g = 0.6kg

I've added 0.65kg and the reading is way off.....

 

[zeo]

is it always this difficult to mix salt water? or is it different between brands?

 

[kkyyllee]

salt water isnt difficult to mix up if u know the right amount to add

 

[FLcracker94]

Usually salt is added at 1/2 cup for every gallon. Thats how much I do and I allways get around 1.024.

 

[sophos9]

salt water isnt difficult to mix up if u know the right amount to add

True!!

So I've just made up 1ltr of tap water with 40g of salt, comes out at 1.024 - guess either the 20ltrs will take some time for the salt to fully dissolve or the salt behaves differently in RO water?

Any help?

 

[kkyyllee]

are you using a hydrometer?

 

[sophos9]

are you using a hydrometer?

Hell no, using a Sybon temperature adjusting refractometer which is fully calibrated

 

[kkyyllee]

then it must not have been fully disolved yet

 

[sophos9]

then it must not have been fully disolved yet

Just gave the container a good old shake, let it settle and measured - its gone up to 1.015 now so its def rising! At 40g per 1ltr, 800g should have done it! I've put in 940g now - doh

 

[sophos9]

Yep... if there was a competition for the dumbest thread, I've won!

Gave it a good shake up again, measured 1.024 which is great....






.... apart from there being a fair bit of undisolved salt left in the bottom

 

[sophos9]

Just worked out how much I OD'd, dumped 3.5ltrs and now topping up with RO. If anyone else buys this salt (it has NO directions), to achieve 1.024 use 40g per 1ltr.

I want to target 1.023 so will use 39g per 1ltr

I hope this thread was erm... entertaining